摘要
MicroRNA是一类存在于动植物体内的重要的、序列高度同源的基因表达转录后调节因子,近来对microRNA不同表达模式和调节作用的研究要求能够快速、灵敏、特异地检测痕量microRNA的方法.利用纳米金银染增强技术建立了一种简单快速的microRNA定量方法,以纳米金标记的寡核苷酸分子作为信号探针,以生物素标记寡核苷酸分子作为捕获探针,经链霉亲和素-生物素作用将靶序列捕获在固相载体酶标孔上,继而通过纳米金催化的银染增强放大效应产生高灵敏的识别信号,记录其吸光度值从而实现microRNA分子的定量.用该方法检测小鼠肝脏,脑组织中miR-122a和miR-128各自的含量及合成miR-122a,结果表明其在良好的线形范围(10pmol/L～10fmol/L)内最低检测限为10fmol/L,能够特异地区别单核苷酸错配的靶microRNA.
MicroRNAs are a class of important post-transcriptional regulators of gene expression in animals and plants. The intensive studies on differential expression and regulatory roles of microRNAs call for sensitive and specific method to detect trace amount of these small size, high sequence homological microRNAs. Here, a simple and reliable method for the quantification of microRNAs was presented. The hybridization products of target microRNAs with biotin-labeled capture probe and oligonucleotides-functioned gold nanoparticles probe were immobilized onto the surface of streptavidin-coated microplate, and the absorbance signals of gold nanoparticles were amplified by silver enhancement. Distribution of miR-122a/miR-128 in mouse brain and liver tissue were detected by this method, and then synthetic miRNA122a was quantified. Results show a lower detect limit of 10 fmol/L with a linear dynamic range from 10 pmol/L to 10 finol/L and a high specificity to discriminate one single oligonucleotide mismatch of the target microRNAs.
出处
《生物化学与生物物理进展》
SCIE
CAS
CSCD
北大核心
2008年第11期1332-1338,共7页
Progress In Biochemistry and Biophysics
基金
国家自然科学基金资助项目(20677018)~~
关键词
MICRORNA
纳米金
银染增强
定量
microRNA, gold nanoparticles, silver enhancement, quantification
